This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A058021 #7 Jul 07 2018 19:19:08
%S A058021 -2,-2,5,11,59,419,839,2503,27701,360337,720703,12252197,232792559,
%T A058021 5354228879,26771144371,80313433159,2329089562799,72201776446757,
%U A058021 144403552893599,5342931457063157,219060189739591153,9419588158802421517,442720643463713815199
%N A058021 Largest prime preceding distinct values of lcm(1,...,m): Max{p|p < A003418(A000961(n))}. To get different LCM values, the last arguments(m) of LCM were selected from A000961.
%e A058021 lcm(1,2,3,4,5,6,7,8)=840 is the 7th term in A000961. Primes preceding it, in descending order, are 839, 829, .... So the corresponding prime in this sequence is 839. The first 2 entries come before lcm(1)=1 and lcm(1,2)=2 as 1-3 = -2 and 2-4 = -2.
%Y A058021 Cf. A000961, A003418, A051451.
%K A058021 sign
%O A058021 0,1
%A A058021 _Labos Elemer_, Nov 15 2000